3GN2

Structure of Pteridine Reductase 1 (PTR1) from TRYPANOSOMA BRUCEI in ternary complex with cofactor (NADP+) and inhibitor (DDD00066730)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.146 
  • R-Value Observed: 0.148 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

One scaffold, three binding modes: novel and selective pteridine reductase 1 inhibitors derived from fragment hits discovered by virtual screening.

Mpamhanga, C.P.Spinks, D.Tulloch, L.B.Shanks, E.J.Robinson, D.A.Collie, I.T.Fairlamb, A.H.Wyatt, P.G.Frearson, J.A.Hunter, W.N.Gilbert, I.H.Brenk, R.

(2009) J Med Chem 52: 4454-4465

  • DOI: 10.1021/jm900414x
  • Primary Citation of Related Structures:  
    2WD7, 2WD8, 3GN2, 3GN1

  • PubMed Abstract: 
  • The enzyme pteridine reductase 1 (PTR1) is a potential target for new compounds to treat human African trypanosomiasis. A virtual screening campaign for fragments inhibiting PTR1 was carried out. Two novel chemical series were identified containing a ...

    The enzyme pteridine reductase 1 (PTR1) is a potential target for new compounds to treat human African trypanosomiasis. A virtual screening campaign for fragments inhibiting PTR1 was carried out. Two novel chemical series were identified containing aminobenzothiazole and aminobenzimidazole scaffolds, respectively. One of the hits (2-amino-6-chloro-benzimidazole) was subjected to crystal structure analysis and a high resolution crystal structure in complex with PTR1 was obtained, confirming the predicted binding mode. However, the crystal structures of two analogues (2-amino-benzimidazole and 1-(3,4-dichloro-benzyl)-2-amino-benzimidazole) in complex with PTR1 revealed two alternative binding modes. In these complexes, previously unobserved protein movements and water-mediated protein-ligand contacts occurred, which prohibited a correct prediction of the binding modes. On the basis of the alternative binding mode of 1-(3,4-dichloro-benzyl)-2-amino-benzimidazole, derivatives were designed and selective PTR1 inhibitors with low nanomolar potency and favorable physicochemical properties were obtained.


    Organizational Affiliation

    Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Pteridine reductaseABCD288Trypanosoma brucei bruceiMutation(s): 0 
Gene Names: PTR1
Find proteins for O76290 (Trypanosoma brucei brucei)
Explore O76290 
Go to UniProtKB:  O76290
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAP
Query on NAP

Download CCD File 
A, B, C, D
NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
C21 H28 N7 O17 P3
XJLXINKUBYWONI-NNYOXOHSSA-N
 Ligand Interaction
AX8
Query on AX8

Download CCD File 
A, B, C, D
1-(3,4-dichlorobenzyl)-1H-benzimidazol-2-amine
C14 H11 Cl2 N3
JBNABAJVIVYIDA-UHFFFAOYSA-N
 Ligand Interaction
ACT
Query on ACT

Download CCD File 
A
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
AX8Ki:  400   nM  Binding MOAD
AX8Ki:  400   nM  BindingDB
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.146 
  • R-Value Observed: 0.148 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.895α = 90
b = 90.778β = 115.85
c = 82.861γ = 90
Software Package:
Software NamePurpose
MOLREPphasing
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-12-29
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2011-09-07
    Changes: Atomic model, Database references